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Silver Diamine Fluoride (SDF) has been documented to effectively arrest dental caries and reduce dental hypersensitivity. SDF promotes remineralization and harden the carious lesion. SDF increases fluoride concentration in saliva and increase the bioavailability of fluoride in saliva. After SDF application, fluoride ion promotes remineralization and silver ion is available for antimicrobial action. Aim: The study aims to determine and compare the amount of fluoride released from various fluoride releasing materials in artificial saliva after 24 hours, 7th day and 14th day of the study. Materials and Methods: 96 premolars free of any caries, fractures, or any other defects were sterilized in 10% formalin for 2 weeks. Then they were rinsed in tap water to remove any fixative from its surface and then stored in deionised distilled water for a period of 30 days prior to testing. Tooth samples were divided into four groups- Group 1: 38% SDF, Group 2: 1.23% APF gel, Group 3: Fluoride varnish and Group 4: Control. All the teeth specimens were blot dried and subjected to their respective material. Fluoride release was analysed using a Fluoride ion-selective electrode after 24 hours, 7days and 14 days of suspension in artificial saliva. Results: Mann-Whitney U Test for inter-group comparison was used for statistical evaluation. 24 Hours fluoride release: The maximum amount of fluoride was released from Fluoride Varnish followed by SDF then APF Gel and least by artificial saliva alone (control) (p

Paper-based digital microfluidic biochips (or P-DMFBs) are becoming highly impelling due to its low-cost and in-place fabrication of electrodes and control wiring on a single piece of paper having an inkjet printer and conductive ink. Despite enormous advantages, several complex design rules also subsist, such as avoidance of induced control interference, minimum separation among the control lines, and congestion-free wiring on a single layer, which is to be correlated leading toward overall feasibility of the design. Several cost raising issues, such as schedule length, control pin count, and wire length, must be considered for attaining a successful fluid-control codesign. Moreover, design gaps exist among the subtasks of the fluid level, control level, and fluid-control design as a whole, which undeniably impose expensive design cycles increasing overall cost. This article builds a machine learning-based model for the pin-constrained P-DMFBs to predict violation in control design beforehand and accordingly guides the fluid-control codesign to tackle important cost-driving issues while attaining congestion- and conflict-free wiring. This model effectively eliminates the design cycles producing a low-cost platform. The predictive model has been evaluated over a balanced data set. Several benchmarks for assessing the performance are studied.

Programmable Microfluidic Devices (PMDs) are revolutionizing the traditional biochemical experiments due to their flexibility of performing various functionalities on a platform without any amendme...

The involvement of Digital Microfluidic Biochips (DMFBs) in the field of disease detection, automated drug discovery, on-chip DNA (Deoxyribonucleic acid) analysis has become well-accepted d...

Paper-based digital microfluidic biochips (PDMFBs) are becoming highly effective among the microfluidic platforms due to its low-cost and in-place fabrication. The designed electrodes and wiring can be fabricated on a piece of paper by an inkjet printer and conductive ink containing carbon nanotube particles (CNTs). However, due to induced control interference, the wires cannot pass by an arbitrary electrode. Each wire that is to be routed possesses its conflict electrode group, which must be avoided for a feasible droplet movement. This paper presents a fluid-control co-design considering several important cost-driving issues like minimization of schedule length, control pin count, and wirelength, together with congestion-free and conflict-free wiring. Observably, design gaps exist among the sub-tasks of the fluid-level, control-level, and fluid-control as a whole, due to their separate considerations. It indeed introduces many design cycles lengthening the design process, and thus increases the overall cost. In this context, this work integrates the sub-tasks as a prior need to obtain a low cost and efficient platform. Several benchmarks have been studied to evaluate the performance.

Droplet-based microfluidic biochips (or DMFBs) are rapidly becoming a revolutionizing lab-on-a-chip technology. Numerous application specific protocols bridging the cross-disciplinary fields necessitate DMFBs as their prime need. The main goal at the fluid level is to minimize bioassay schedule length. Also, for a safe assay outcome, contamination among droplet routes must be avoided. Size restriction of a chip and reconfigurable nature of the operational modules in DMFB introduce contaminated cells which necessarily require washing as an urgent need. As the sub-tasks of fluid level possess their own constraints for a successful DMFB design, rip-up and reiteration of sub-tasks may become unavoidable if all of those constraints are not satisfied mutually. To achieve a shorter time for chip realization a crucial need in fluid-level design is to avoid rip-up and re-iteration; hence, design convergence is to be incorporated that collectively considers the fluid-level sub-tasks, instead of solving them individually. Thus, this paper focuses on the fluid level of DMFBs while considering design convergence, contamination avoidance, and washing issues. Obtained results are compared with several existing benchmarks.

The design process for digital microfluidic biochips (DMFBs) is becoming more complex due to the growing need for essential bio-protocols. A number of significant fluid- and chip-level synthesis tools have been offered previously for designing an efficient system. Several important cost drivers like bioassay schedule length, total pin count, congestion-free wiring, total wire length, and total layer count together measure the efficiency of the DMFBs. Besides, existing design gaps among the sub-tasks of the fluid and chip level make the design process expensive delaying the time-to-market and increasing the overall cost. In this context, removal of design cycles among the sub-tasks is a prior need to obtain a low-cost and efficient platform. Hence, this paper aims to propose a fluid-chip co-design methodology in dealing with the consideration of the fluid-chip cost drivers, while reducing the design cycles in between. A simulation study considering a number of benchmarks has been presented to observe the performance.

Production of correct bioassay outcome is the foremost objective in digital microfluidic biochips (or DMFBs). In high-frequency DMFBs, continuous actuation of electrodes leads to malfunctioning or even breakdown of the system. The improper functioning of a biochip tends to produce erroneous results. On the other hand, while transporting droplets, the residues may get stuck to electrode walls and cause contamination to other droplets. To ensure proper assay outcome, washing becomes mandatory, whose incorporation may delay the bioassay completion time significantly. Furthermore, each wash droplet possesses a capacity constraint within which the residues can be washed off successfully. Evidently, the design objectives possess a large degree of trade-offs among themselves and must be attacked to prepare an efficient platform. Here, the authors propose a complete fluid-level synthesis considering all the essential goals together instead of dealing with them in isolation. The presented approach effectively handles the trade-off scenarios and provides flexibility to the designer to decide the threshold of the individual optimisation objective leading to the construction of a good-quality solution as a whole. The performance is evaluated over several benchmark bioassays.

The primary tooth has numerous functions and is important in a child's development. Pediatric endodontic treatment has a very important role in maintaining oral health of the child. However, the morphology of root canals in deciduous teeth usually leads to complications in root canal therapy. To improve the success in endodontic, a thorough knowledge of the root canal morphology is essential.The aim of this study is to determine the thorough in vitro, morphological evaluation of root canal system of human primary molars using multidetector computed tomography.A total of 64 human primary maxillary and mandibular molars without any macroscopic root resorption were selected and divided into four groups. The samples were arranged in wax block, and the scanning was done on the computed tomography scanne (GE light speed 16 slice CT).The images were grabbed by the computer as a raw image and reformatted in a GE Advantage workstation version 4.2 (GE healthcare) with the help of Denta Scan (GE healthcare) software and volume rendering was done.Descriptive statistical analysis (Student's t-test) was performed to calculate the means with corresponding standard deviations. A value of P ≤ 0.05 was taken to be statistically significant.It enlightens the clinicians view to access the morphological variations of the root canals for the effective pediatric endodontic treatment.The images showed the complexity of the root canals of the primary mandibular molars and also the several capabilities of the CT scan in advance endodontic research in primary teeth were observed.

Obesity is a recognized worldwide epidemic with increasing prevalence in developing nations. Studies have shown that obesity is an independent risk factor for the development of chronic kidney disease (CKD) besides its link with diabetes mellitus and hypertension. We evaluated the renal status of obese patients using both the established [creatinine (Cr)] and new (cystatin C) markers of renal function. This was a cross-sectional study. Fifty-nine consenting adults attending the clinic for routine medical checks were recruited for this study. They were divided into obese and non-obese based on their body mass index. Serum from specimens collected were assayed for Cr and cystatin C. CKD equations were used to estimate glomerular filtration rate based on Cr (eGFR-Cr), cystatin C (GFR-Cystatin), and Cr/cystatin C (GFRCr/cystatin) while modification of diet in renal disease equation was also used to eGFR-Cr. The eGFR results generated were compared in assessing renal function. The obese participants and the controls were age-matched (50.6 ± 9.7 vs. 50.7 ± 7.8 years, P = 0.2). The obese participants had a significantly higher serum cystatin C (1.3 ± 0.7 vs. 0.9 ± 0.4 mg/L, P < 0.001) and significantly lower eGFR-cystatin C (75.4 ± 38.9 mL/min/1.73 m2 vs. 90.9 ± 25.1 mL/min/1.73 m2, P < 0.001) than the controls, respectively. There was a significant difference between the eGFR-Cr and eGFR-cystatin C in the obese participants (97.4 ± 21.4 vs. 75.4 ± 38.9 mL/min/1.73 m2), P = 0.019). The results showed that mild renal impairment exists among obese participants. Routine assessment is recommended to pre-empt deterioration in renal function. Cystatin C appears to be a better marker of renal function in obesity than serum Cr.

Digital microfluidic biochips are reforming many areas of biochemistry, biomedical sciences, as well as microelectronics. It is renowned as lab-on-a-chip for its appreciation as a substitute for laboratory experiments. Nowadays, for emergency purposes and to ensure cost efficacy, multiple assay operations are essential to be carried out simultaneously. In this context, parallelism is of utmost importance in designing biochip while the size of a chip is a constraint. Hence, the objective of this study is to enhance the performance of a chip in terms of its throughput, electrode utilisation, and pin count as well. Here, the authors have considered some of the most familiar assay requirements where a sample is to be analysed using different reagents, and identify some parameter(s) of the sample(s) under consideration. Moreover, sample preparation is a vital task in digital microfluidic biochip; thus, dilution of different samples up to different concentrations using buffer (neutral) fluid is a crucial issue. In this design, the authors effectively perform this task in parallel in a number of sub-regions of a given restricted sized chip using an array based partitioning pin-assignment technique while taking care of the cross contamination problem. The design has been verified for some significant real life assay examples.

Digital microfluidic based biochip manoeuvres on the theory of microfluidic technology, having a broad variety of applications in chemistry, biology, environmental monitoring, military etc. Being concerned about the technological advancement in this domain, we have focused on equilateral triangular electrodes based DMFB systems. Accepting the associated design issues, here, we have addressed many facets of such electrodes regarding their structural and behavioural issues in comparison to the existing square electrodes. As the requisite voltage reduction is a key challenging design issues, to implement all the tasks using triangular electrodes that are possible in square electrode arrays as well, is a tedious job. Furthermore, to deal with this new design deploying triangular electrodes, we have analyzed all the necessary decisive factors including fluidic constraints to ensure safe droplet movements and other modular operations together with mixing and routing. Moreover, an algorithm has been developed to find a route for a given source and destination pair in this newly designed DMFB. Finally, we have included a comparative study between this new design and the existing one while encountering the above mentioned issues.

Defective microfluidic chip increases the assay completion and total turnaround time and it is the main reason of deviation of the actual result of assay operation. In online testing, the test droplets are moving out of step with each other. Again testing of DMFB is NP-hard in nature. Using Euler path based test technique, we can test the whole chip but we cannot apply Hamiltonian path based test method in case of equilateral triangular electrode array due to routing constraints in triangular DMFB. A graph-based test planning technique for online testing is proposed in this paper. Considering the active parts of the chip, like mixer and store cell, as obstacle in the triangular microfluidic array, we test the chip during the assay operation running in some portions of the array. Here, we focus on Euler path based test technique for catastrophic fault detection.

Successful root canal therapy requires an in-depth knowledge of root canal morphology.False assumptions about the root canal anatomy of teeth may lead to misdiagnosis, missed canals, improper debridement and breakage of root canal instruments during root canal treatment. The objective of this paper was to review the various methods used to study and understand root canal systems. The complexity of root canal morphology presents a challenge to any clinician. Any attempt to perform root canal therapy must be preceded with a thorough understanding of the anatomy of both the pulp chamber and the root canal system.Several methods have been used to examine the root canal system ranging from in vitro methods such as sectioning of teeth, metal castings to advanced in vivo tomographic imaging, along with the use of magnificationBangladesh Journal of Dental Research and Education Vol.5(2) 2015: 59-63

Aeromonas caviae is commonly recognized as a low-virulence gram-negative bacillus. Human infections due to Aeromonas caviae may present as a variety of diseases, such as wound infection, acute gastroenteritis, septicemia, pneumonia, septic arthritis or endocarditis. It has rarely been reported as a causative organism of septicemia. We present a successfully treated case of post- traumatic necrotizing soft tissue infection with sepsis of nosocomial origin due to multidrug resistant (MDR) Aeromonas caviae in a 51-year-old immunocompetent individual. Phenotypic confirmation was done by VITEK 2 COMPACT Advance Expert System.

Pasteurella canis is a Gram-negative, nonmotile, coccobacillus belonging to the family Pasteurellaceae, erstwhile known to be penicillin-sensitive. It is a known causative organism for zoonotic infections especially skin and soft tissue infections after animal bite. It is known to cause respiratory tract infection among immunocompromised patients. Here we present a case of community-acquired lower respiratory tract infection (LRTI) in an apparently immunocompetent middle aged female patient caused by multidrugresistant (MDR) Pasteurella canis biovar2. We suggest the organism to be included in differential diagnosis in such cases.

Background: Ventilator-associated pneumonia (VAP) is an infection of the lung that develops 48 h or longer after mechanical ventilation. Objectives: The present study was aimed to find out the bacteriological profile of VAP along with the resistance pattern of bacteriological isolates. Materials and Methods: A prospective observational study was conducted from January 2013 to May 2014 among 791 patients admitted in critical care units of our tertiary care hospital. After selection by applying inclusion and exclusion criteria endotracheal aspirates were collected from ventilated patients. Samples were subjected to further processing by Gram-staining, culture, biochemical testing and antibiogram. Results : Out of 791 patients admitted in intensive care unit in this tertiary care hospital with VAP 540 (68.2%) patients were culture positive. Pseudomonas aeruginosa was most commonly isolated pathogen of both early onset and late onset VAP. In early VAP Acinetobacter baumannii showed 62.5% metallo-beta-lactamase (MBL) positivity. P. aeruginosa showed 27.5% MBL positivity, whereas in late onset VAP, 71.4% A. baumannii isolates and 75.8% P. aeruginosa isolates showed MBL positivity, respectively. Conclusion : Simple prevention of aspiration, sterilization of equipments, hand washing of personnel can reduce VAP in hospital care setting.

Microfluidic biochip is a lab-on-a-chip system that replaces conventional laboratory experiments. Digital Microfluidic Biochip (DMFB) handles liquids as discrete droplets, and offers highly reconfigurable and scalable technology. DMFB combines electronics with biology opening the new application areas of Microelectronics, Biochemistry, and Biomedical sciences. A new application area of DMFB using equilateral triangular electrodes instead of square electrodes has been proposed, considering the design issues and the fluidic constraints while performing all the modular operations. The improvement of sample-reagent mixing procedure is a key challenge issue in bioassay implementation as mixing is the most dominating operation in DMFB; hence, the Triangular DMFB (TEDMB) system leads over the existing DMFB system. In this paper, we have presented a study of TEDMB mixers and developed mixing library for TEDMB synthesis.

Management of infectious wounds, particularly chronic wounds and burn injuries, is a matter of global concern. Worldwide estimates reveal that, billions of dollars are being spent annually for the management of such chronic ailments. Evidently, bacterial biofilms pose a greater problem in the effective management of infection in chronic wounds, since most of the currently available antibiotics are unable to act on the microorganisms residing inside the protected environment of the biofilms. Accordingly, in the present study, we have attempted to evaluate the anti-biofilm properties of human placental extract (PLX) and also other virulence factors that are mediated via the quorum sensing (QS) signalling system. PLX is well known for its anti inflammatory action and it has been shown earlier some anti microbial and enzymatic activity also. PLX was found to produce significant inhibition of biofilm formation and also decreased the levels of pyoverdin and pyocyanin. The microscopic analysis (both light microscopy and atomic force microscopy) of biofilms was also used for substantiating the findings from spectrophotometric (crystal violet estimation) and fluorescence analysis (resazurin uptake). PLX pre-treatment decreased the hydrophobicity of gram-positive and gram negative cells, indicating the effect of placental extract on adherence property of planktonic cell, serving as an indicator for its antibiofilm effect on microorganisms. The reduced extracellular DNA (eDNA) content in biofilm matrix following treatment with PLX also indicates the effectiveness of placenta extract on bacterial adherence, which in turn serves as evidence substantiating the antibiofilm effects of the PLX. Furthermore, PLX was also found to be significantly effective in the in vitro wound biofilm model. Thus the present study, the first of its kind with PLX, establishes the therapeutic benefit of the same particularly in infected wounds, opening up newer avenue for further exploration.

Due to inherent reconfigurable capability, digital microfluidic biochips (DMFBs) have been a prime platform for critical medical diagnosis, real time bioassays, and lab-on-chip experiments. However, dependability is an urgent need to decide the correct outcome from a bioassay execution. To make a DMFB dependable in high frequency applications, a single electrode must not be frequently used as it may result in over-actuation problem. An over-actuated cell degrades over time and results a failure. Current fluid-level synthesis method only considers in minimizing the total completion time of the assay. Besides, recent technologies use abundant re-execution and perform costly online synthesis whenever such a fault is discovered. Two papers address the dependability issue and propose a placement solution. Here, we present a complete fluid-level synthesis to prepare binding, scheduling, placement, and routing solutions for a given bioassay. The concerned problem is proved to be NP-complete. A dynamic programming formulation is followed to obtain a solution in pseudo-polynomial time. Several benchmarks are used to evaluate the proposed method.

ABSTACT: BACKGROUND: Septicaemia is a life threatening complication of severely burned patients. Among many organisms invading blood stream Pseudomonas aeruginosa is a well-known for its powerful antibiotic resistance mechanisms which increasingly limit the choices for treatment. Among many such resistance mechanisms it is the metallo-beta-lactamase (MBL) which confers resistance to Carbapenem group of antibiotics, one of the final resorts to fight them. The present study was undertaken to detect MBL producing P. aeruginosa using phenotypic method from blood samples of burned patients as well as to know their drug sensitivity pattern. MATERIALS AND METHODS: For this purpose 67 Pseudomonas aeruginosa isolates from blood samples of admitted burned patients were subjected to susceptibility testing to antipseudomonal drugs by disc diffusion test and those found to be Carbapenem resistant were subjected to Imipenem - EDTA combined disk synergy test for MBL detection. RESULT: Out of 67 isolates of P.aeruginosa, 19 (28.4%) were found to be Carbapenem resistant and 11 (16.4%) were MBL producers. A particularly important feature was that the MBL producers were highly resistant to the antibiotics tested than the non-producers. However all of them were susceptible to Colistin and Polymixin B. CONCLUSION: This study has made us to think that a constant vigil and careful selection of antibiotics are necessary to keep prevalence of MBL producing P.aeruginosa in check. The accurate identification and reporting of MBL producing P. aeruginosa will aid infection control practitioners in preventing the spread of these multidrug-resistant isolates.

Characterization of an aqueous extract of human placenta, used as a licensed drug for wound healing, leads to the identification of several bioactive components including polydeoxyribonu-cleotides (PDRNs). PDRNs are mixture of DNA fragments of different molecular weight. A spectro-fluorimetric method of quantitation of PDRNs in the aqueous extract of human placenta by using ethidium bromide (EtBr) has been described here. It has been demonstrated by thin layer chromatography (TLC) followed by reversed phase HPLC that EtBr binds specifically with the PDRN fraction of the multi-component extract. The binding specificity of EtBr has been verified by the analysis of emission spectra of the extract. A concentration of 0.29 μg/ml EtBr exhibits a linear range of standard CT-DNA from 0.5 - 5 μg/ml of buffer (R2 = 0.992). The same concentration of EtBr shows a linear range of measurements of placenta extract from 5 - 35 μl/ml of buffer (R2 = 0.976). The points of the curve were the average of three sets where maximum variation observed was ±3%. PDRN content of the extract has been estimated based on the resultant fluorescence emission (after background correction) with respect to the standard calibration curve of calf thymus DNA (CT-DNA). Estimation of PDRN in a large number of batches of placenta extract (n = 100) has been done. The statistical analysis of the estimation was found to be significant and the lower and upper levels of PDRN were 158.30 and 239.03 μg/ml of the extract respectively. This easy-to-use method of estimation of PDRN in multi-component biological extract is reported for the first time. This will help in quantitation of PDRNs for other biological extracts.

Here, we have proposed a statistical framework based on a novel bat algorithm inspired particle swarm optimisation algorithm for the reconstruction of gene regulatory networks from temporal gene expression data. The recurrent neural network formalism has been implemented to extract the underlying dynamics from time series microarray datasets accurately. The proposed swarm intelligence framework has been used for optimising the parameters of the recurrent neural network model. Preliminary research with the proposed methodology has been done on a small, artificial network and the experimental (in vivo) microarray data of the SOS DNA repair network of Escherichia coli. Results obtained suggest that the proposed methodology can infer the underlying network structures with a better degree of success.

An aqueous extract of human placenta, used as wound healer, shows stabilization of trypsin against autodigestion as one of the peptides of the extract binds very strongly with the protease. Trypsin retains 40% of activity at constant level between 20 and 26 days in presence of the extract against complete inactivation in its absence. Inhibition of esterolytic activity and inability to react with p-nitrophenyl-p'-guanidinobenzoate, HCl, an active site directed reagent, by trypsin in presence of a peptide fraction of the extract indicated blocking of the catalytic site of the enzyme. Rayleigh scattering, size-exclusion HPLC, fluorescence resonance energy transfer, and surface plasmon resonance show that fibronectin type III-like peptide present in the extract interacts with trypsin. The peptide-trypsin complex is dissociated in presence of high concentration of substrates. Thus, regulation of trypsin activity by the placental extract is evident.

The healing properties of placental extract are well established in various skin conditions, including chronic wounds, pressure ulcers and burns. However, its biochemical composition and mechanisms of action are still largely unknown